Enter the world of hi-tech mobile phones


Cell Phone Magic - A Leap From The Radio Telephone

My introduction to the grand daddy of cellavailable.The cell phone system is divided
phones was while I was working as a Forestinto small cells, which allows greater
Fire Lookout man, in the early 1980s. One offrequency reuse in an area, so that millions
my colleagues worked on a lookout tower, inof customers can use cell phones at the same
radio range of a radio telephone repeatertime. Today modern cell phones can
tower. So he could use a radio telephone,communicate on 1,664 frequencies or more!
and free up more of the Forest ServiceEach cell occupies about 10 square miles.
frequency that I used. His radio telephoneThere can be 56 people talking on their cell
was about the size of a lap top. Cell phonesphone at one time within the area of a cell.
are really down-sized radio telephones.TheThe cell phone uses a much less powerful
advantage cell phones have today, over theradio signal than a radio telephone. The
old Radio telephone, is that they are muchlarger number of cell phone towers makes this
smaller and easier to use than the old radiopossible.Another advantage of using a low
telephones. Cell phones use very littlepower radio signal of 3 watts is that it
battery power compared, to a radio telephone.fades to near nothing past the edge of the
This fact has helped the cell phonecell; so the same frequencies can be reused
designers reduce their size to that of anin the neighbouring cells. As you travel you
object that can fit in your pocket.The radioare switched automatically from the cell
telephone was big and had to have a verytower you are moving away from to the next
powerful radio signal to reach the few radiobest located tower in the area you are going
towers that existed. The radio signal ittoward. As you travel your cell phone sends
transmitted had to be powerful enough toout a code signal which identifies itself,
reach a tower 40 or 50 miles away.Cell phonesyou the user, and the service provider. Your
today are much smaller, and easier to use.cell phone is always communicating with the
Both people on a cell phone call can talk atcell tower and its service provider. This is
once. Both listen at the same time. Whendone to keep track of which cell it is
using a radio telephone, only one person canlocated in, how strong the signal strength is
talk at a time, while the other person canreceived, and transmitted, and to determine
only listen. Since there are many cellif the cell you are in, is owned by your
towers in the system, many more people canprovider, or another company. A person can
use cell phones, than could use the old radiotravel for hundreds of miles and hold a
telephones. Radio telephones only had aboutconversation the entire time using cellular
25 frequencies, available to use. Today eachtechnology.
cell has about 56 voice channels



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